In WO 2010/000289 a method and apparatus for mining and processing sea bed sediment is provided. The apparatus consists of a crawler vehicle for travelling across the sea bed, which disturbs sediment. The vehicle includes a suction system to recover the disturbed sediment. The present invention describes a suction mouth for the suction system of such a mining tool.
U.S. Pat. No. 4,232,903 describes an ocean mining system for mining manganese nodules. A subsea mining vehicle is propelled by Archimedes screws. The vehicle uses a rake and conveyor system to pick up nodules, which are then washed, crushed and passed through a riser to a surface vessel.
Various excavation tools from dredging operations are known for mining materials such as sand, silt or gravel. Typically such materials are recovered using a drag head mounted on a trailing suction hopper dredger. The drag head is pulled along and sucks up material from behind the dredger. This is suitable for use in relatively shallow water depths and where the sediment layer is able to support the weight of the dredger. For softer sediment layers a suction mouth mounted on the front of a vehicle is required so that the suction mouth can be pushed forward into the sediment layer. This limits disturbance of the sediment by the propulsion system used.